What if you forgot to bring your Boga-Grip along and you got a big one that you are gonna C&R?... would you ever know it's weight?Even without the help of a scale like Boga we can estimate and calculate the weight and size of the fish using a formula: L x G Squared / 800L= Length (inches)G= Girth (inches)Will give a the fish's weight in lbs.If you do not have a measuring tape you could include items like a dollar note or your feet in the photo for subsequent calculations.